"It's not bad news," Reds manager Dusty Baker said. "It's the best news it could be for bad news. There's nothing structural or nothing in the joint."
The medical report Baker was given said that the inflammation of the ulnar nerve in Volquez's elbow caused the numbness in his fingers that ended Monday's start vs. the Cardinals after only one inning.
Volquez hadn't pitched since May 16 because of mid-back spasms that put him on the DL for the first time in his career. He threw in two side bullpen sessions while he was out and reported no arm trouble -- before or after the back injury.
"He might have felt something and thought it might have been normal soreness or something," Baker said. "If every time you felt something and you sat out, most of us would never play. He had never said anything to us about it."
During the first inning of the Reds' 5-3 win on Monday, Volquez reported numbness while facing second batter Colby Rasmus. It went away but it was enough to cause alarm and leave the game after completing the inning with 24 pitches thrown. Five members of the Reds bullpen pitched the eight remaining innings. In nine starts this season, Volquez is 4-2 with a 4.35 ERA.
Last season, when he was a 17-game winner and a first-time All-Star for Cincinnati, Volquez threw a career-high 196 innings. He then made the choice to pitch a few innings in winter ball in his native Dominican Republic to get ready for the World Baseball Classic.
"We were a bit fearful it was something because of the workload he had in winter ball and the WBC, getting ready so fast," Baker said. "We were very apprehensive about the whole thing."
Baker was not ready to name a starter to take Volquez's next rotation turn on Saturday against the Cubs.
"Not yet," Baker said. "We have an idea but we have to wait just in case something happens. Whoever it is, you don't want that person thinking about it for four or five days either."
At Louisville, lefty Matt Maloney pitched a three-hit shutout on Monday and is 4-3 with a 2.00 ERA through 10 starts. He would be able to pitch on his normal rest and it would be his big league debut.
The Reds could also opt to move Bronson Arroyo up and pitch him on three days' rest. Arroyo started vs. St. Louis on Tuesday. Homer Bailey, who came up for one unsuccessful start for the Reds already this season, also pitched on Tuesday for Louisville.
Burton was just sent down on Monday to make room for Volquez after he was activated from the DL, but never got as far as his room at the team hotel near Busch Stadium when his phone rang.
"They told me, 'Don't go,'" Burton said. "So it's like it never happened."
Burton, who turned 28 on Tuesday, had a 6.33 ERA in 20 appearances and let seven of his 10 inherited runners score. He was sent down to get regular work and build his confidence, but the emergency superseded that plan for now.
"I'm just looking at it as, no matter where I'm at, here or there, I just have to get things going mentally and see some success," said Burton, who didn't have to wait out the 10-day rule to return from the Minors because of Volquez's injury. "Then I'll be fine, no matter where it is. I'm just glad to be here with this group of guys and get a chance to get out there and get locked back in."